ZIP code 91001: Altadena, CA
ZIP code 91001 is in Altadena (99% of residents) and Pasadena (1.5%), in Los Angeles County, California. It is in California's 28th congressional district. Its state senate district is State Senate District 25; its state house district is Assembly District 41.
See it on the mapAll of California
City and county
| City or town | Share of ZIP residents |
|---|---|
| Altadena | 99% |
| Pasadena | 1.5% |
| County | Share of ZIP residents |
|---|---|
| Los Angeles County | 100% |
| Town or county subdivision | Share of ZIP residents |
|---|---|
| Pasadena CCD | 100% |
| South Antelope Valley CCD | <0.1% |
Congressional district
| Congressional district | Share of ZIP residents |
|---|---|
| California's 28th congressional district (CA-28) | 100% |
Elected officials
| Office | Member | Contact | Share of residents |
|---|---|---|---|
| U.S. Representative (CA-28) | Judy Chu (D) | 202-225-5464 | 100% |
| U.S. Senator | Adam B. Schiff (D) | 202-224-3841 | statewide |
| U.S. Senator | Alex Padilla (D) | 202-224-3553 · contact form | statewide |
| State Senator (State Senate District 25) | Sasha Pérez (Democratic) | 818-409-0402 | 100% |
| Assembly Member (Assembly District 41) | John Harabedian (Democratic) | 626-351-1917 | 100% |
Elected in 2024 under CA's previous congressional map; this district's lines changed for the 120th Congress (seated January 3, 2027).
Officials serving now (members of Congress until January 3, 2027). Sources: State legislators: Open States (public domain); Members of Congress: the @unitedstates project, congress-legislators (CC0).
Local government
- Altadena website: https://altadenatowncouncil.org/
- Altadena laws: search for the Altadena, California code of ordinances
- Pasadena website: https://pasadena.gov
- Pasadena council: Pasadena City Council
- Pasadena laws: search for the Pasadena, California code of ordinances
- Los Angeles County website: https://lacounty.gov
- Los Angeles County laws: search for the Los Angeles County, California code of ordinances
State legislative districts
| State senate district | Share of ZIP residents |
|---|---|
| State Senate District 25 | 100% |
| State house district | Share of ZIP residents |
|---|---|
| Assembly District 41 | 100% |
Voting precincts
12 voting precincts overlap ZIP 91001. Map them, with each precinct's share of the ZIP's residents.
Get this in your AI agent
Your agent can get these cities, counties, districts and precincts with their shares, and their GeoJSON boundaries, from Boundary Atlas. Add https://atlas-production-d344.up.railway.app/mcp to Claude, ChatGPT, Cursor or Codex (free, no key; how), then:
related_geographies(id="us:zcta:91001")
ZIP 91001 here is the Census Bureau's ZIP Code Tabulation Area, which approximates the USPS ZIP Code; PO-box-only ZIPs have none. Districts are the maps in force for the November 3, 2026 election.